The invention relates to an electromagnetically actuatable gas valve for metering a gaseous fuel into a suction tract of an engine, in particular a gas or diesel/gas engine. The invention furthermore relates to a method for increasing the seal of an electromagnetically actuatable gas valve.
Electromagnetically actuatable gas valves for injecting gaseous fuels into a suction tract of an engine are widely known. The use of such valves can involve combining them to form a central injection unit for supplying a plurality of cylinders of the engine with gaseous fuel (central gas injection—“CGI”) or providing at least one separate gas valve for each cylinder (multi-point injection—“MPI”).
A gas valve of the type in question is disclosed by German Laid-Open Application DE 199 05 721 A1, for example. In order to provide a large passage cross section combined with short switching and response times, there is a proposal in this document for a gas valve, which is designed as a flat seat valve. It has a level valve seat and a sealing element having at least one level sealing surface facing the valve seat. This design is intended to allow valve cross sections of up to several 100 mm2, which it should be possible to reliably switch while simultaneously achieving short switching times. In this case, the valve seat is preferably formed by at least two concentric sealing strips, which define an annular passage cross section, which can be covered by a—preferably annular—sealing element. A plurality of annular passage cross sections of the valve seat can preferably be covered by a plurality of circumferential webs of the sealing element, of which at least two in each case are connected to one another by at least one radial web. The resulting grid structure of the sealing element is intended to ensure sufficient mechanical strength. In order, furthermore, to counteract deformations due to forces of the opening and closing system acting on the sealing element, provision is furthermore made for the opening and closing forces to be transmitted to the sealing element via a plunger. The plunger is intended to bring about large-area introduction of the force and thereby prevent deformation moments, thus ensuring the sealing effect.